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Engine running like crap on ethanol

Mark1972

Mark1972

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Hey guys. I've been away for some time, so I'm sure this has been discussed ad nauseum. My engine(440, Edelbrock AVS2 800) was built to run on Shell 91, which here in Canada had no ethanol until last year. This year my engines not been running well, and while there are ways to remove the ethanol, and then replace with non-ethanol octane booster, I simply don't have the time/resources to do that. What changes would I possibly need to make to get my car running smoothly again? It stumbles, it revs up and down on its own, especially when slowing down. It bogs on take off. When I shut it off hot, it sometimes hesitates to start until it's turned over a few times. I checked the timing and it's still set at 35 degrees total. I've never used the vaccum advance. It's never run this poor before. What would be a checklist for me to follow to diagnose what's going on?
 
How old is the gas? Did the car sit for a long time with the ethanol in the carburetor? If it is old gas and it sat, the carb may be all full of gooey stuff, or the gas is bad.
 
Can you buy 87 non ethanol ? If it is a fuel octane prob and 87 is available you may be able to blend in some AV gas or a booster to get back to 91 or close enough you can tune your way out, back off timing ect.
Like posted ^^^ if it has set for a couple years you may want to pop the top on that eddy.
 
Sounds like you have issues more than gas. Vacuum leak, plugged carb, or ignition issues.
 
Ethanol laced gas does no favors to a carburetor. I ran one tankful of that dog piss in my car. It started what you are experiencing. Stumbling, surging and bogging. Upon inspection when I pulled the top off of the carb, I noticed the accelerator pump was half eaten away. The kit was only a couple months old. I replaced the pump and have never had another problem with it. I don't run ethanol in anything I own that has a carburetor. Even my weed whacker gets premium 91 now. If you can't find gas without ethanol, I don't have much help for you. Someone told me that some of the newer carb kits have updated accelerator pumps that can stand up to the alcohol but I have no evidence and have not had to go that route yet. I know it is coming though. Good Luck!
 
Edelbrock:
Thunder Series AVS2 Carbs will work with Ford automatic overdrive trans (AOD) when used with Lokar bracket SRK-4000. Edelbrock carburetors are not calibrated for or compatible with alcohol, race or E85 pump fuel. The use of alcohol or E85 in your Edelbrock carburetor will damage your carburetor and void your warranty.

Except it did work, until it didn't. See if you can buy an E-85 rebuild kit, it's probably a piece of rubber or gasket plugging something.
 
sam dupont said:
Edelbrock:
Thunder Series AVS2 Carbs will work with Ford automatic overdrive trans (AOD) when used with Lokar bracket SRK-4000. Edelbrock carburetors are not calibrated for or compatible with alcohol, race or E85 pump fuel. The use of alcohol or E85 in your Edelbrock carburetor will damage your carburetor and void your warranty.

Except it did work, until it didn't. See if you can buy an E-85 rebuild kit, it's probably a piece of rubber or gasket plugging something.
Click to expand...

@Mark1972 never said he was running E85. Edelbrock AVS2's accept blended fuels up to 10% ethanol. It's right in the manual. We have no more ethanol free gas in Canada, Chevron 94 now has 10% in it too. I have an AVS2 650 and it doesn't seem to mind the gas. I agree with others, you may have another issue. For problems restarting when hot, check your fuel lines, may be boiling the fuel if they are too close to the block or resting on other hot areas. Put one of the heat insulator spacers under the AVS2, it cured my heat soak issues. Barely even gets warm to the touch now.
 
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The AVS2 is a really good carb out of the box, but I'd also recommend, like others said, to pop the top and clean it out if it's been sitting for a long time and old gas. While you are in there, check the float heights, as they are 100% not going to be where they need to be (ask me how I know). Off idle bog is tuneable.
 
We have plenty of ethanol mixed in here in CA and other than the occasional percolation/hard starting issues in summer (which I've taken care of) my beast runs just fine with it. Oh yeah it'd be better without any ethanol, but....it's what we get.

I'm with da' eldubb on this one...look for crap in the carb and fuel filter(s) too. Maybe a good time for a cleaning. Inspect all your lines/hoses, looking for any signs of cracking or stiffening. Modern fuel can degrade some types of regular rubber fuel hose and those pieces can end up where they shouldn't. Easy stuff first.
Check thoroughly for vacuum leaks anywhere they can appear. Carb base, any capped off ports, pcv etc. Revving up and down by itself/hunting can also be a symptom of that.
I'm sure there are others that will offer more things to look at but that's where I'd start based on the behavior, good luck and let us know how it goes!
 
Don67Satellite said:
@Mark1972 never said he was running E85. Edelbrock AVS2's accept blended fuels up to 10% ethanol. It's right in the manual. We have no more ethanol free gas in Canada, Chevron 94 now has 10% in it too. I have an AVS2 650 and it doesn't seem to mind the gas. I agree with others, you may have another issue. For problems restarting when hot, check your fuel lines, may be boiling the fuel if they are too close to the block or resting on other hot areas. Put one of the heat insulator spacers under the AVS2, it cured my heat soak issues. Barely even gets warm to the touch now.
Click to expand...
e10 or e85, both the same as far as the parts know.
 
A 1958 International V8 will run on straight alcohol. A 1978 International will run on straight alcohol. I have run e85 to save money with no adjustments to the carb.
They built them all to run on LP gas, so ethanol blends don't hurt valves and I've never had an issue with carb parts dissolving. IH has always had top quality stuff.

The accelerator pump cup is fine with 10%, but 20% melts it?
 
sam dupont said:
A 1958 International V8 will run on straight alcohol. A 1978 International will run on straight alcohol. I have run e85 to save money with no adjustments to the carb.
They built them all to run on LP gas, so ethanol blends don't hurt valves and I've never had an issue with carb parts dissolving. IH has always had top quality stuff.

The accelerator pump cup is fine with 10%, but 20% melts it?
Click to expand...
Okay, well now I see the cause for confusion is that you don't know what you're talking about.
E85 is (up to) 85% ethanol, not the other way around and yes it will eat certain parts if they aren't suitable not to mention the tuning differences.
 
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the carb can not just rest atop the intake that transfers heat . so i've been using carb spacers made up of multi gasket thin spacer and so on the stack , this will keep the carb cooler , and the most important item is to block off the exhaust heat transfer ports m if you have them in the heads . intake gaskets are out there to block those ports . this is what it took to keep the fuel from boiling in the bowls and vaporing down the carb and intake , and it might need retuning and new gaskets and pump to handle the crappy new fuel . been dealing with this type fuel in calif for years now . and even with a hot cam this afb carbs does just fine , spring , summer , fall and winter . but an electric choke is needed , well a choke is needed . these two emgines have carter afb type carbs .

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If it has the blue accelerator pump the 10% will eat it. Bad accelerator pump can cause several symptoms. Get the orange vitron one that's ethanol resistant.

I run 10% during the summer months, non ethanol for winter storage. With each tank of 10% I'll add a few ounces of Stabil 360. It's formulated for ethanol and helps to stabilize it. My carbs always look sparkling inside the bowls.
 
IMO.....It depends on the percentage of ethanol in the gasoline blend. Ethanol has half the heating value, or energy (BTU's) as an equivalant quantity of gasoline. It also burns slower. Your problem may be solved by richening the fuel mixture, by changing metering rods and jets and adjusting (increasing) the spark advance characteristics to allow for a slower burn, slightly faster rate and possibly total amount of crankshaft degrees. Check the spark plug coloring to see how your changes effect the engine. The addition of a heat insulator spacer under the carb should help with a hot soak fuel evaporation issues. You MAY have to increase mixture by 10-15% depending on percentage of ethanol in the gasoline......
BOB RENTON
 
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